Fiber Optic Terminal Box and Splice Closure Guide: Types and Selection
Fiber optic terminal boxes and splice closures are essential components in FTTH and fiber optic network installations. They protect fiber splices and provide cable termination points.
Fiber Optic Terminal Box
A fiber optic terminal box (also called FTTH terminal box or wall box) is installed at the subscriber premises. It houses the fiber splice point between the drop cable and the pigtail, protects the splice, and provides an adapter interface for the ONT connection. Terminal boxes typically support 1-4 fiber ports and are wall-mountable.
Fiber Optic Splice Closure
A fiber optic splice closure (also called splice case or joint closure) protects fusion splices in outdoor environments. They are used in aerial, underground, and direct burial installations. Splice closures come in horizontal and vertical designs, supporting 12-288 fiber splices.
Key Differences
Terminal boxes are for indoor use at the subscriber end, while splice closures are for outdoor cable jointing and distribution. Terminal boxes are smaller (1-4 ports), while splice closures handle multiple cables with higher fiber counts.
Selection Guide
For FTTH installations: choose a terminal box that matches your drop cable type and provides sufficient splice tray space. For outdoor cabling: select a splice closure with proper IP rating (IP68 for direct burial), compatible with your cable diameter, and adequate splice tray capacity.
